Bleed-Resistant, Oil-Extended Olefin Block Copolymer Composition with Surface-Active Agent

ABSTRACT

The present disclosure provides an oil-extended olefin block copolymer composition. The oil-extended olefin block copolymer composition includes an olefin block copolymer, an oil, and a surface-active agent and may optionally include an olefin-based polymer. The oil-extended olefin block copolymer composition advantageously exhibits reduced, or no, oil-bleed.

BACKGROUND

Olefin block copolymers (OBC) are useful for producing soft compoundssuch as soft touch articles. The block architecture of the OBC resultsin good tensile strength, compression set and temperature resistance. Tomake soft touch compositions (i.e., compositions with a low durometervalue and/or a low Shore A hardness value), OBC is mixed with an oil. Asthe amount of oil is increased, so too increases the likelihood ofoil-bleed. Oil-bleed is problematic because it produces undesirablehaptics in articles fabricated from these compounds.

A need therefore exists for a soft, oil-extended OBC composition withreduced oil-bleed.

SUMMARY

The present disclosure is directed to oil-extended OBC compositions withreduced, or no, oil-bleed. The present compositions contain asurface-active agent that is an oil-bleed inhibitor. The presence of thesurface-active agent maintains the softness of the composition, andsimultaneously reduces, or eliminates, oil-bleed.

The present disclosure provides a composition. In an embodiment, thecomposition is an oil-extended olefin block copolymer composition andincludes an olefin block copolymer, an oil, and a surface-active agent.

The present disclosure provides another composition. In an embodiment,the composition is an oil-extended olefin block copolymer compositionand includes an olefin block copolymer, an olefin-based polymer, an oil,and a surface-active agent

An advantage of the present disclosure is the provision of a soft,oil-extended OBC composition with reduced, or no, oil-bleed.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows examples of various grey scales used for the normalizedoil-bleed index in accordance with an embodiment of the presentdisclosure.

DETAILED DESCRIPTION

The present disclosure provides an oil-extended olefin block copolymer(OBC) composition. An “oil-extended OBC composition,” as used herein, isan OBC composition that contains an (i) OBC and (ii) at least 25 wt %oil, based on the total weight of the composition. In an embodiment, theoil-extended OBC composition contains at least 30 wt %, or at least 40wt % to 50 wt %, or 60 wt %, or 70 wt % oil. In an embodiment, anoil-extended olefin block copolymer composition is provided and includesan olefin block copolymer, an oil, and a surface-active agent.

1. OBC

The term “olefin block copolymer” or “OBC” is an ethylene/α-olefinmulti-block copolymer and includes ethylene and one or morecopolymerizable α-olefin comonomer in polymerized form, characterized bymultiple blocks or segments of two or more polymerized monomer unitsdiffering in chemical or physical properties. The terms “interpolymer”and copolymer” are used interchangeably herein. In some embodiments, themulti-block copolymer can be represented by the following formula:

(AB)_(n)

where n is at least 1, preferably an integer greater than 1, such as 2,3, 4, 5, 10, 15, 20, 30, 40, 50, 60, 70, 80, 90, 100, or higher, “A”represents a hard block or segment and “B” represents a soft block orsegment. Preferably, As and Bs are linked in a substantially linearfashion, as opposed to a substantially branched or substantiallystar-shaped fashion. In other embodiments, A blocks and B blocks arerandomly distributed along the polymer chain. In other words, the blockcopolymers usually do not have a structure as follows.

AAA-AA-BBB-BB

In still other embodiments, the block copolymers do not usually have athird type of block, which comprises different comonomer(s). In yetother embodiments, each of block A and block B has monomers orcomonomers substantially randomly distributed within the block. In otherwords, neither block A nor block B comprises two or more sub-segments(or sub-blocks) of distinct composition, such as a tip segment, whichhas a substantially different composition than the rest of the block.

The olefin block copolymer includes various amounts of “hard” and “soft”segments. “Hard” segments are blocks of polymerized units in whichethylene is present in an amount greater than about 95 weight percent,or greater than about 98 weight percent based on the weight of thepolymer. In other words, the comonomer content (content of monomersother than ethylene) in the hard segments is less than about 5 weightpercent, or less than about 2 weight percent based on the weight of thepolymer. In some embodiments, the hard segments include all, orsubstantially all, units derived from ethylene. “Soft” segments areblocks of polymerized units in which the comonomer content (content ofmonomers other than ethylene) is greater than about 5 weight percent, orgreater than about 8 weight percent, greater than about 10 weightpercent, or greater than about 15 weight percent based on the weight ofthe polymer. In some embodiments, the comonomer content in the softsegments can be greater than about 20 weight percent, greater than about25 weight percent, greater than about 30 weight percent, greater thanabout 35 weight percent, greater than about 40 weight percent, greaterthan about 45 weight percent, greater than about 50 weight percent, orgreater than about 60 weight percent.

The soft segments can be present in an OBC from about 1 weight percentto about 99 weight percent of the total weight of the OBC, or from about5 weight percent to about 95 weight percent, from about 10 weightpercent to about 90 weight percent, from about 15 weight percent toabout 85 weight percent, from about 20 weight percent to about 80 weightpercent, from about 25 weight percent to about 75 weight percent, fromabout 30 weight percent to about 70 weight percent, from about 35 weightpercent to about 65 weight percent, from about 40 weight percent toabout 60 weight percent, or from about 45 weight percent to about 55weight percent of the total weight of the OBC. Conversely, the hardsegments can be present in similar ranges. The soft segment weightpercentage and the hard segment weight percentage can be calculatedbased on data obtained from DSC or NMR. Such methods and calculationsare disclosed in U.S. patent application Ser. No. 11/376,835, entitled“Ethylene/α-Olefin Block Inter-polymers,” filed on Mar. 15, 2006, in thename of Colin L. P. Shan, Lonnie Hazlitt, et. al. and assigned to DowGlobal Technologies Inc., the disclosure of which is incorporated byreference herein in its entirety.

The term “crystalline” if employed, refers to a polymer that possesses afirst order transition or crystalline melting point (Tm) as determinedby differential scanning calorimetry (DSC) or equivalent technique. Theterm may be used interchangeably with the term “semicrystalline”. Theterm “amorphous” refers to a polymer lacking a crystalline melting pointas determined by differential scanning calorimetric (DSC) or equivalenttechnique.

The term “multi-block copolymer” or “segmented copolymer” is a polymercomprising two or more chemically distinct regions or segments (referredto as “blocks”) preferably joined in a linear manner, that is, a polymercomprising chemically differentiated units which are joined end-to-endwith respect to polymerized ethylenic functionality, rather than inpendent or grafted fashion. In an embodiment, the blocks differ in theamount or type of incorporated comonomer, density, amount ofcrystallinity, crystallite size attributable to a polymer of suchcomposition, type or degree of tacticity (isotactic or syndiotactic),region-regularity or regio-irregularity, amount of branching (includinglong chain branching or hyper-branching), homogeneity or any otherchemical or physical property. Compared to block interpolymers of theprior art, including interpolymers produced by sequential monomeraddition, fluxional catalysts, or anionic polymerization techniques, thepresent OBC is characterized by unique distributions of both polymerpolydispersity (PDI or Mw/Mn or MWD), block length distribution, and/orblock number distribution, due, in an embodiment, to the effect of theshuttling agent(s) in combination with multiple catalysts used in theirpreparation.

In an embodiment, the OBC is produced in a continuous process andpossesses a PDI from about 1.7 to about 3.5, or from about 1.8 to about3, or from about 1.8 to about 2.5, or from about 1.8 to about 2.2. Whenproduced in a batch or semi-batch process, the OBC possesses PDI fromabout 1.0 to about 3.5, or from about 1.3 to about 3, or from about 1.4to about 2.5, or from about 1.4 to about 2.

In addition, the olefin block copolymer possesses a PDI fitting aSchultz-Flory distribution rather than a Poisson distribution. Thepresent OBC has both a polydisperse block distribution as well as apolydisperse distribution of block sizes. This results in the formationof polymer products having improved and distinguishable physicalproperties. The theoretical benefits of a polydisperse blockdistribution have been previously modeled and discussed in Potemkin,Physical Review E (1998) 57 (6), pp. 6902-6912, and Dobrynin, J. Chem.Phys. (1997) 107 (21), pp 9234-9238.

In an embodiment, the present olefin block copolymer possesses a mostprobable distribution of block lengths. In an embodiment, the olefinblock copolymer is defined as having:

(A) Mw/Mn from about 1.7 to about 3.5, at least one melting point, Tm,in degrees Celsius, and a density, d, in grams/cubic centimeter, whereinthe numerical values of Tm and d correspond to the relationship:

Tm>−2002.9+4538.5(d)−2422.2(d)², and/or

where d is from 0.850 g/cc, or 0.860, or 0.866 g/cc, or 0.87 g/cc, or0.880 g/cc to 0.89 g/cc, or 0.91 g/cc, or 0.925 g/cc, and Tm is from113° C., or 115° C., or 117° C., or 118° C. to 120° C., or 121° C., or125° C.; and/or

(B) Mw/Mn from about 1.7 to about 3.5, and is characterized by a heat offusion, ΔH in J/g, and a delta quantity, ΔT, in degrees Celsius definedas the temperature difference between the tallest DSC peak and thetallest Crystallization Analysis Fractionation (“CRYSTAF”) peak, whereinthe numerical values of ΔT and ΔH have the following relationships:

ΔT>−0.1299(ΔH)+62.81 for ΔH greater than zero and up to 130 J/g

ΔT≧48° C. for ΔH greater than 130 J/g

wherein the CRYSTAF peak is determined using at least 5 percent of thecumulative polymer, and if less than 5 percent of the polymer has anidentifiable CRYSTAF peak, then the CRYSTAF temperature is 30° C.;and/or

(C) elastic recovery, Re, in percent at 300 percent strain and 1 cyclemeasured with a compression-molded film of the ethylene/α-olefininterpolymer, and has a density, d, in grams/cubic centimeter, whereinthe numerical values of Re and d satisfy the following relationship whenethylene/α-olefin interpolymer is substantially free of crosslinkedphase:

Re>1481−1629(d); and/or

(D) has a molecular weight fraction which elutes between 40° C. and 130°C. when fractionated using TREF, characterized in that the fraction hasa molar comonomer content of at least 5 percent higher than that of acomparable random ethylene interpolymer fraction eluting between thesame temperatures, wherein said comparable random ethylene interpolymerhas the same comonomer(s) and has a melt index, density and molarcomonomer content (based on the whole polymer) within 10 percent of thatof the ethylene/α-olefin interpolymer; and/or

(E) has a storage modulus at 25° C., G′(25° C.), and a storage modulusat 100° C., G′(100° C.), wherein the ratio of G′(25° C.) to G′ (100° C.)is in the range of about 1:1 to about 9:1.

The olefin block copolymer may also have:

(F) a molecular fraction which elutes between 40° C. and 130° C. whenfractionated using TREF, characterized in that the fraction has a blockindex of at least 0.5 and up to about 1 and a molecular weightdistribution, Mw/Mn, greater than about 1.3; and/or

(G) average block index greater than zero and up to about 1.0 and amolecular weight distribution, Mw/Mn greater than about 1.3. It isunderstood that the olefin block copolymer may have one, some, all, orany combination of properties (A)-(G).

Suitable monomers for use in preparing the present OBC include ethyleneand one or more addition polymerizable monomers other than ethylene.Examples of suitable comonomers include straight-chain or branchedα-olefins of 3 to 30, preferably 3 to 20, carbon atoms, such aspropylene, 1-butene, 1-pentene, 3-methyl-1-butene, 1-hexene,4-methyl-1-pentene, 3-methyl-1-pentene, 1-octene, 1-decene, 1-dodecene,1-tetradecene, 1-hexadecene, 1-octadecene and 1-eicosene; cyclo-olefinsof 3 to 30, preferably 3 to 20, carbon atoms, such as cyclopentene,cycloheptene, norbornene, 5-methyl-2-norbornene, tetracyclododecene, and2-methyl-1,4,5,8-dimethano-1,2,3,4,4a,5,8,8a-octahydronaphthalene; di-and polyolefins, such as butadiene, isoprene, 4-methyl-1,3-pentadiene,1,3-pentadiene, 1,4-pentadiene, 1,5-hexadiene, 1,4-hexadiene,1,3-hexadiene, 1,3-octadiene, 1,4-octadiene, 1,5-octadiene,1,6-octadiene, 1,7-octadiene, ethylidenenorbornene, vinyl norbornene,dicyclopentadiene, 7-methyl-1,6-octadiene,4-ethylidene-8-methyl-1,7-nonadiene, and 5,9-dimethyl-1,4,8-decatriene;and 3-phenylpropene, 4-phenylpropene, 1,2-difluoroethylene,tetrafluoroethylene, and 3,3,3-trifluoro-1-propene.

In an embodiment, the OBC has a density of less than or equal to about0.90 g/cc, or less than about 0.89 g/cc. Such low density OBCs aregenerally characterized as amorphous, flexible and having good opticalproperties, e.g., high transmission of visible and UV-light and lowhaze.

In an embodiment, the olefin block copolymer has a density from 0.85g/cc to 0.88 g/cc.

In an embodiment, the olefin block copolymer has a melt index (MI) fromabout 0.1 g/10 min to about 10 g/10, or from about 0.1 g/10 min to about1.0 g/10 min, or from about 0.1 g/10 min to about 0.5 g/10 min asmeasured by ASTM D 1238 (190° C./2.16 kg).

The olefin block copolymer has a 2% secant modulus greater than zero andless than about 150, or less than about 140, or less than about 120, orless than about 100, MPa as measured by the procedure of ASTM D 882-02.

The present OBC has a melting point of less than about 125° C. Themelting point is measured by the differential scanning calorimetry (DSC)method described in WO 2005/090427 (US2006/0199930), the entire contentof which is incorporated by reference herein.

In an embodiment, the oil-extended OBC composition includes from 20 wt %to 60 wt % OBC, or from 20 wt %, or 30 wt % to 35 wt %, or 40 wt %, or50 wt %, or 60 wt % OBC.

2. Oil

The oil-extended OBC composition includes an oil. The oil can be anaromatic oil, a mineral oil, a naphthenic oil, paraffinic oil, atriglyceride-based vegetable oil such as castor oil, a synthetichydrocarbon oil such as polypropylene oil, a silicone oil, or anycombination thereof. Nonlimiting examples of suitable oil includemineral oil sold under the trade names HYDROBRITE® 550 (Sonneborn),Kaydol (Sonneborn), Britol 50T (Sonneborn), Clarion 200 (Citgo), andClarion 500 (Citgo).

In an embodiment, the oil-extended OBC composition contains at least 20wt %, or at least 30 wt %, or at least 40 wt %, or at least 45 wt % to55 wt %, or 70 wt % oil. Weight percent is based on the total weight ofthe oil-extended OBC composition.

3. Surface-Active Agent

The oil-extended OBC composition includes a surface-active agent. Theterm “surface-active agent,” as used herein, is a compound that reducesthe surface energy of the composition by migrating to the surface of thecomposition, the surface-active agent having a lower surface energy thanthe oil or the OBC. Bounded by no particular theory, it is believed thesurface-active agent in the present composition reduces oil bleed byreducing the surface energy of the polymer surface, thereby reducingpropensity of the oil to collect on the polymer surface. Provision ofsufficient surface-active agent yields a low energy surface to theentire polymer surface, achieving the desired effect of reduced, or no,oil bleed.

A. Fluorosurfactant

In an embodiment, the surface-active agent is a fluorosurfactant. A“fluorosurfactant,” as used herein is a hydrocarbon chain with at leastone hydrogen atom replaced by a fluorine atom, with the carbon chainalso containing at least one functional group. Functional groups includehydroxyl, carboxyl, and carbonyl groups. In an embodiment, thesurface-active agent is a perfluorosurfactant. A “perfluorosurfactant,”as used herein, is a hydrocarbon chain with all the hydrogen atomsreplaced by fluorine atoms, with the carbon chain also containing atleast one functional group. In an embodiment, the carbon chain of thefluorosurfactant or the perfluorosurfactant is a C₄-C₁₀ carbon chain.

In an embodiment, the surface-active agent is a perfluorosurfactant andhas one, some, or all of the following properties:

a specific gravity from 1.2 to 1.5;

a weight-average molecular weight from 500 g/mol to 1500 g/mol; and

a surface tension (deionized water at 25° C.) less than 30 dyne (dyn)/cmat 0.01% concentration surfactant in water.

In an embodiment, the perfluorosurfactant is an ethoxylated nonionicperfluorosurfactant, in which the perfluoro-carbon chains are C₄-C₆carbon chains. The ethoxylated nonionic perfluorsurfactant does notproduce, decompose, or otherwise degrade to perfluorooctanoic acid. Theweight-average molecular weight of the ethoxylated nonionicperfluorsurfactant is from 700 g/mol to 1100 g/mol. The ethoxylatednonionic perfluorosurfactant has a specific gravity from 1.3 to 1.4, anda surface tension (deionized water at 25° C.) less than 25 dyn/cm at0.01% surfactant in water concentration. A nonlimiting example of asuitable ethoxylated nonionic perfluorsurfactant is sold under the tradename CAPSTONE FS3100, available from E. I. du Pont de Nemours andCompany.

In an embodiment, the composition includes from 0.01 wt %, or 0.1 wt %,or 0.5 wt %, or 1.0 wt % to 1.5 wt %, or 2.0 wt % of the(fluorosurfactant or perfluorosurfactant), based on the total weight ofthe oil-extended OBC composition.

B. Polysiloxane Surfactant

In an embodiment, the surface-active agent is a polysiloxane surfactant.A “polysiloxane surfactant” as used herein, is a polysiloxane chain,with the polysiloxane chain also containing at least one functionalgroup. Functional groups include, hydroxyl, carboxyl, ether, andcarbonyl groups. The polysiloxane surfactant has one, some, or all ofthe following properties:

a specific gravity from 0.9 to 1.1; and

a viscosity from 20 to 2500 centistoke at 25° C.

In an embodiment, the polysiloxane surfactant is a poly(ethyleneglycol-b-dimethyl siloxane) copolymer. In a further embodiment, thepoly(ethylene glycol-b-dimethyl siloxane) copolymer has a specificgravity from 1.0 to 1.1 and a viscosity from 150 to 400 centistoke at25° C. A nonlimiting example of a suitable polysiloxane surfactant isDC-57 available from Dow Corning.

In an embodiment, the polysiloxane surfactant is a component of apre-mixture. The pre-mixture includes the polysiloxane surfactant and analkylene glycol, such as ethylene glycol.

In a further embodiment, the polysiloxane surfactant is halogen-free.That is, the polysiloxane surfactant (or the aforementioned pre-mixturecontaining same) is void of fluorine, chlorine, bromine and iodine.

In an embodiment, the oil-extended OBC composition includes from 0.01 wt%, or 0.1 wt %, or 0.5 wt %, or 1.0 wt % to 1.5 wt %, or 2.0 wt % of thepolysiloxane surfactant, based on the total weight of the composition.

In an embodiment, the oil-extended OBC composition contains from about30 wt % to about 70 wt % olefin block copolymer, from about 30 wt % toabout 70 wt % oil, and from about 0.01 wt % to about 2.0 wt %surface-active agent.

In an embodiment, the oil extended OBC composition includes:

-   -   from 25 wt %, or 26 wt %, or 30 wt % to 33 wt %, or 35 wt %, or        39 wt %, or 40 wt %, or 45 wt % OBC;    -   from 35 wt %, or 40 wt %, or 45 wt % to 49 wt %, or 50 wt %, or        55 wt %, or 60 wt % oil; and    -   from 0.01 wt %, or 0.1 wt %, or 0.013 wt %, or 0.016 wt %, or        1.0 wt % to 1.5 wt %, or 2.0 wt % surface-active agent.

In an embodiment, the oil-extended OBC composition has a Shore Ahardness from 5, or 10, or 20 to 30, or 35, or 40, or 50.

In an embodiment, the oil-extended OBC composition contains a filler.Nonlimiting examples of suitable filler include talc, calcium carbonate,chalk, calcium sulfate, clay, kaolin, glass, mica, wollastonite,feldspar, aluminum silicate, silica, calcium silicate, alumina, hydratedalumina such as alumina trihydrate, glass microsphere, ceramicmicrosphere, thermoplastic microsphere, barite, wood flour, glassfibers, carbon fibers, marble dust, cement dust, magnesium oxide,magnesium hydroxide, antimony oxide, zinc oxide, barium sulfate,titanium dioxide, and titanates.

In an embodiment, the oil-extended OBC composition is phthalate-free.

Applicants have surprisingly discovered that provision of asurface-active agent unexpectedly reduces oil-bleed while maintainingsoftness in oil-extended OBC compositions. The term “oil-bleed-out” or“oil-bleed” is the phenomenon whereby oil migrates from the interior ofa polymeric component to the surface of the polymeric component.Oil-bleed makes the surface sticky and/or slippery. Oil-bleed typicallyresults in adverse “feel” (haptics) and/or adverse “optics” (visualappearance). The term “oil exudation” is the process of oil moving froman interior location to a surface of a polymeric component. Oilexudation yields oil-bleed. In other words, oil-bleed is the end resultof oil exudation. Oil-bleed is accelerated by elevated temperatures.

Oil-bleed is evaluated by way of a normalized oil-bleed index (NOBI).NOBI is an optical measurement of the amount of oil absorbed oncigarette paper from an oil-containing polymeric composition. NOBI iscalculated according to the following equation:

Normalized Oil-bleed Index=100·(% grey scale sample−% grey scalecontrol)/(100−% grey scale control)

The term “% grey scale sample” is the percent grey scale measured on theaged sample and “% grey scale control” is a measurement on an unageduntreated sheet of cigarette paper. The term “% grey scale” is equal tothe percentage of black pixels on a binary (black and white) digitalimage of the cigarette paper. The image can be obtained for example bydigital scanning or digitally photographing a sheet of cigarette paper.NOBI has a range from 0-100. When NOBI=100, the paper is saturated andthe test does not register oil-bleed beyond that level. When NOBI=0, thepaper has no oil markings and its appearance is similar to that ofuntreated cigarette paper. Normal experimental error may result in ahigher value of NOBI for a control sample (untreated sheet of cigarettepaper) than for a treated sample with low oil absorption, thus creatingnegative values of NOBI.

FIG. 1 shows four degrees of grey scale with conversion to acorresponding NOBI index (using the NOBI equation above) as set forth inTable 1 below.

TABLE 1 % Grey Scale (FIG. 1) NOBI Index 20.1% 0 34.6% 18.1 51.6% 39.4 100% 100

In an embodiment, the oil-extended OBC composition has a NOBI index ofless than 30, or from 0, or 1, or 2, or 5 to less than 30, or less than20, or less than 15, or less than 10 after 24 hours at 23° C.

In an embodiment, the oil-extended OBC composition has a NOBI index ofless than 30, or from 0, or 1, or 2, or 5 to less than 30, or less than20, or less than 15, or less than 10 after 1 week at 23° C.

In an embodiment, the oil-extended OBC composition has a NOBI index ofless than 30, or from 0, or 1, or 2, or 5 to less than 30, or less than20, or less than 15, or less than 10 after 3 weeks at 23° C.

In an embodiment, the oil-extended OBC composition has a NOBI indexafter 3 weeks at 23° C. from 0, or 1, or 5 to 12, or 15, or less than20.

In an embodiment, the oil-extended OBC composition has a Shore Ahardness from 5, or 10 to 50, or 30, or 25, or 20.

The disclosure provides another composition. In an embodiment, anoil-extended polymeric composition is provided and includes an olefinblock copolymer, from 70 phr to 250 phr oil, and from 0.05 phr to 5 phrsurface-active agent. The composition has a Shore A hardness from 5 to50. The composition also has a normalized oil-bleed index of less thanor equal to 30, or less than or equal to 20 after three weeks at 23° C.

The term “phr” or “parts per hundred,” as used herein, is based on acomposition having 100 phr OBC. In other words, the composition contains100 phr OBC. The term “phr” provides a way to identify the uniquerelationship between the OBC, the oil, and the surface-active agentregardless of other optional components that may be present in thecomposition.

In an embodiment, the oil-extended OBC composition includes from 150 phrto 235 phr oil.

In an embodiment, the oil-extended OBC composition contains from 0.5 phrto 5 phr surface-active agent.

In an embodiment, the oil-extended OBC composition has a NOBI index ofless than 30, or from 0, or 1, or 2, or 5 to less than 30, or less than20, or less than 15, or less than 10 after 24 hours (1 day) at 23° C.

In an embodiment, the oil-extended OBC composition has a NOBI index ofless than 30, or from 1, or 2, or 5 to less than 30, or less than 20, orless than 15, or less than 10 after 1 week at 23° C.

In an embodiment, the oil-extended OBC composition has a NOBI index ofless than 30, or from 0, or 1, or 2, or 5, to less than 30, or less than20, less than 15, or less than 10 after 3 weeks at 23° C.

In an embodiment, the oil-extended OBC composition has a NOBI indexafter 3 weeks at 23° C. from 0, or 1, or 5 to 12, or 15, or less than20.

In an embodiment, the oil-extended OBC composition has a Shore Ahardness from 5, or 10 to 50, or 40, or 30, or 25, or 20.

The disclosure provides another composition. In an embodiment, anoil-extended olefin block copolymer composition is provided and includesan olefin block copolymer (OBC), an olefin-based polymer, an oil, and asurface-active agent. The OBC and the surface active agent can be anyrespective OBC and surface active agent as previously described herein.

4. Olefin-Based Polymer

The oil-extended OBC composition includes an olefin-based polymer. Theolefin-based polymer is different than the olefin block copolymer. Theterm, “olefin-based polymer,” as used herein, refers to a polymer thatcomprises, in polymerized form, a majority amount of olefin monomer, forexample ethylene or propylene (based on the weight of the polymer), andoptionally may comprise one or more comonomers.

In an embodiment, the olefin-based polymer is a propylene-based polymer.The term, “propylene-based polymer,” as used herein, refers to a polymerthat comprises, in polymerized form, a majority amount of propylenemonomer (based on the weight of the polymer), and optionally maycomprise one or more comonomers. The propylene-based polymer may be (i)a Ziegler-Natta catalyzed propylene copolymer comprising repeating unitsderived from propylene and one or more α-olefins having from 2 (ethyleneis considered an α-olefin for purposes of this disclosure) or from 4 to10 carbon atoms; (ii) a metallocene-catalyzed propylene copolymercomprising repeating units derived from propylene and one or moreα-olefins having 2 or from 4 to 10 carbon atoms; (iii) aZiegler-Natta-catalyzed propylene homopolymer; (iv) ametallocene-catalyzed propylene homopolymer; and combinations thereof.

In an embodiment, the propylene-based polymer is a propylenehomopolymer.

In an embodiment, the oil-extended OBC composition contains 10 wt % to40 wt % OBC, 5 wt % to 25 wt % propylene homopolymer, 15 wt % to 60 wt %oil, and 0.01 wt % to 2.0 wt % surface-active agent. Weight percent isbased on total weight of the oil-extended composition.

In an embodiment, the olefin-based polymer is an ethylene-based polymer.The term, “ethylene-based polymer,” as used herein, refers to a polymerthat comprises, in polymerized form, a majority amount of ethylenemonomer (based on the weight of the polymer), and optionally maycomprise one or more comonomers. The ethylene-based polymer may be (i) aZiegler-Natta catalyzed ethylene copolymer comprising repeating unitsderived from ethylene and one or more α-olefins having from 3 to 10carbon atoms; (ii) a metallocene-catalyzed ethylene copolymer comprisingrepeating units derived from ethylene and one or more α-olefins havingfrom 3 to 10 carbon atoms; (iii) a Ziegler-Natta-catalyzed ethylenehomopolymer; (iv) a metallocene-catalyzed ethylene homopolymer; andcombinations thereof.

In an embodiment, the olefin-based polymer is an ethylene/α-olefincopolymer. The term “ethylene/α-olefin copolymer,” as used herein,refers to a copolymer that comprises, in polymerized form, a majorityamount of ethylene monomer (based on the weight of the copolymer), andan α-olefin, as the only two monomer types. The ethylene/α-olefincopolymer can include ethylene and one or more C₃-C₂₀ α-olefincomonomers. The comonomer(s) can be linear or branched. Nonlimitingexamples of suitable comonomers include propylene, 1-butene, 1-pentene,4-methyl-1-pentene, 1-hexene, and 1-octene. The ethylene/α-olefincopolymer can be prepared with either Ziegler-Natta, chromium-based,constrained geometry or metallocene catalysts in slurry reactors, gasphase reactors or solution reactors. The ethylene/α-olefin copolymer isa random copolymer and is distinct from the OBC which has a blockintra-molecular architecture.

In an embodiment, the ethylene/α-olefin copolymer is a high densityethylene/α-olefin copolymer having a density range with a lower limitfrom 0.94 g/cc, or greater than 0.94 g/cc, or 0.95 g/cc to an upperlimit of 0.96 g/cc, or 0.970 g/cc. In a further embodiment, the highdensity ethylene/α-olefin copolymer has a melt index from 0.5 g/10 minto 10.0 g/10 min.

In an embodiment, the oil-extended OBC composition has a NOBI index ofless than 30, or from 0, or 1, or 2, or 5 to less than 30, or less than20, or less than 15, or less than 10 after 24 hours at 23° C.

In an embodiment, the oil-extended OBC composition has a NOBI index ofless than 30, or from 1, or 2, or 5 to less than 30, or less than 20, orless than 15, or less than 10 after 1 week at 23° C.

In an embodiment, the oil-extended OBC composition has a NOBI index ofless than 30 or from 1, or 2, or 5 to less than 30, or less than 20, orless than 15, or less than 10 after 3 weeks at 23° C.

In an embodiment, the oil-extended OBC composition has a NOBI indexafter 3 weeks at 23° C. from 0, or 1, or 5 to 12, or 15, or less than20.

Any of the foregoing oil-extended olefin block copolymer compositionsmay optionally include one or more of the following additives: slipagents, anti-blocking agents, plasticizers oils, antioxidants, UVstabilizers, colorants or pigments, fillers, lubricants, antifoggingagents, flow aids, coupling agents, cross-linking agents, nucleatingagents, solvents, flame retardants, antistatic agents, and anycombination thereof. The total amount of the additive(s) can range fromabout greater than 0, or about 0.001%, or about 0.01%, or about 0.1%, orabout 1%, or about 10% to about 80%, or about 70%, or about 60%, orabout 50%, or about 40% of the total weight of the polymer blend.

In an embodiment, any of the foregoing oil-extended olefin blockcopolymer composition is free of silica or is otherwise void of silica.

In an embodiment, any of the foregoing oil-extended olefin blockcopolymer composition is free of wax or is otherwise void of wax.

Any of the foregoing oil-extended olefin block copolymer compositionsmay comprise two or more embodiments disclosed herein.

Any of the foregoing oil-extended olefin block copolymer compositionsmay be a component of one or more of the following articles: moldedarticles, extruded articles, overmolded grips, baby bibs, gaskets. Theoil-extended OBC compositions disclosed herein can be used tomanufacture durable articles for the automotive, construction, medical,food and beverage, electrical, appliance, business machine, and consumermarkets. In some embodiments, the oil-extended OBC composition is usedto manufacture flexible durable parts or articles selected from toys,grips, soft touch handles, bumper rub strips, floorings, auto floormats, wheels, casters, furniture and appliance feet, tags, seals,gaskets such as static and dynamic gaskets, automotive doors, bumperfascia, grill components, rocker panels, hoses, linings, officesupplies, seals, liners, diaphragms, tubes, lids, stoppers, plungertips, delivery systems, kitchen wares, footwear, shoe bladders and shoesoles. In other embodiments, the oil-extended OBC composition can beused to manufacture durable parts or articles that require a hightensile strength and low compression set. In further embodiments, theoil-extended OBC composition can be used to manufacture durable parts orarticles that require a high upper service temperature and low modulus.

DEFINITIONS

All references to the Periodic Table of the Elements herein shall referto the Periodic Table of the Elements, published and copyrighted by CRCPress, Inc., 2003. Also, any references to a Group or Groups shall be tothe Groups or Groups reflected in this Periodic Table of the Elementsusing the IUPAC system for numbering groups. Unless stated to thecontrary, implicit from the context, or customary in the art, all partsand percents are based on weight. For purposes of United States patentpractice, the contents of any patent, patent application, or publicationreferenced herein are hereby incorporated by reference in their entirety(or the equivalent US version thereof is so incorporated by reference),especially with respect to the disclosure of synthetic techniques,definitions (to the extent not inconsistent with any definitionsprovided herein) and general knowledge in the art.

Any numerical range recited herein, includes all values from the lowervalue to the upper value, in increments of one unit, provided that thereis a separation of at least 2 units between any lower value and anyhigher value. As an example, if it is stated that the amount of acomponent, or a value of a compositional or a physical property, suchas, for example, amount of a blend component, softening temperature,melt index, etc., is between 1 and 100, it is intended that allindividual values, such as, 1, 2, 3, etc., and all subranges, such as, 1to 20, 55 to 70, 197 to 100, etc., are expressly enumerated in thisspecification. For values which are less than one, one unit isconsidered to be 0.0001, 0.001, 0.01 or 0.1, as appropriate. These areonly examples of what is specifically intended, and all possiblecombinations of numerical values between the lowest value and thehighest value enumerated, are to be considered to be expressly stated inthis application. In other words, any numerical range recited hereinincludes any value or subrange within the stated range.

The terms “blend” or “polymer blend,” as used herein, is a blend of twoor more components (or two or more polymers). Such a blend may or maynot be miscible (not phase separated at molecular level). Such a blendmay or may not be phase separated. Such a blend may or may not containone or more domain configurations, as determined from transmissionelectron spectroscopy, light scattering, x-ray scattering, and othermethods known in the art.

The term “composition,” as used herein, includes a mixture of materialswhich comprise the composition, as well as reaction products anddecomposition products formed from the materials of the composition.

The term “comprising,” and derivatives thereof, is not intended toexclude the presence of any additional component, step or procedure,whether or not the same is disclosed herein. In order to avoid anydoubt, all compositions claimed herein through use of the term“comprising” may include any additional additive, adjuvant, or compoundwhether polymeric or otherwise, unless stated to the contrary. Incontrast, the term, “consisting essentially of” excludes from the scopeof any succeeding recitation any other component, step or procedure,excepting those that are not essential to operability. The term“consisting of” excludes any component, step or procedure notspecifically delineated or listed. The term “or”, unless statedotherwise, refers to the listed members individually as well as in anycombination.

Normalized oil-bleed index (NOBI) is an optical measurement of theamount of oil absorbed on cigarette paper from an oil-containing polymercomposition. NOBI is a phenomenological measurement related not only tothe rate of oil migration to the surface but also the rate of oilabsorption by the paper and the translucence induced thereby. NOBI isnot directly proportional to the mass of the oil on the surface.

The term “polymer” is a macromolecular compound prepared by polymerizingmonomers of the same or different type. “Polymer” includes homopolymers,copolymers, terpolymers, interpolymers, and so on. The term“interpolymer” means a polymer prepared by the polymerization of atleast two types of monomers or comonomers. It includes, but is notlimited to, copolymers (which usually refers to polymers prepared fromtwo different types of monomers or comonomers, terpolymers (whichusually refers to polymers prepared from three different types ofmonomers or comonomers), tetrapolymers (which usually refers to polymersprepared from four different types of monomers or comonomers), and thelike.

Test Methods

¹³C NMR is performed on OBC polymer to determine weight percent hardsegment/soft segment.

A. ¹³C NMR Sample Preparation

The sample is prepared by adding approximately 2.7 g of stock solvent to0.21 g sample in a 10 mm NMR tube, and then purging in a N₂ box for 2hours. The stock solvent is made by dissolving 4 g of PDCB in 39.2 g ofODCB with 0.025M chromium acetylacetonate (relaxation agent). The sampleis dissolved and homogenized by heating the tube and its contents at140-150° C.

B. Data Acquisition Parameters

The data are collected using a Bruker 400 MHz spectrometer equipped witha Bruker Dual DUL high-temperature CryoProbe. The data are acquiredusing 320 transients per data file, a 7.3 sec pulse repetition delay (6sec delay+1.3 sec acq. time), 90 degree flip angles, and inverse gateddecoupling with a sample temperature of 120° C. All measurements aremade on non-spinning samples in locked mode. Samples are homogenizedimmediately prior to insertion into the heated (125° C.) NMR Samplechanger, and are allowed to thermally equilibrate in the probe for 15minutes prior to data acquisition.

Differential Scanning Calorimetry (DSC)

Differential Scanning calorimetry (DSC) is used to measure crystallinityin the polymers (e.g., ethylene-based (PE) polymers). About 5 to 8 mg ofpolymer sample is weighed and placed in a DSC pan. The lid is crimped onthe pan to ensure a closed atmosphere. The sample pan is placed in a DSCcell, and then heated, at a rate of approximately 10° C./min, to atemperature of 180° C. for PE (230° C. for PP). The sample is kept atthis temperature for three minutes. Then the sample is cooled at a rateof 10° C./min to −60° C. for PE (−40° C. for PP), and kept isothermallyat that temperature for three minutes. The sample is next heated at arate of 10° C./min, until complete melting (second heat). The percentcrystallinity is calculated by dividing the heat of fusion (H_(f)),determined from the second heat curve, by a theoretical heat of fusionof 292 J/g for PE (165 J/g, for PP), and multiplying this quantity by100 (for example, % cryst.=(H_(f)/292 J/g)×100 (for PE)).

Unless otherwise stated, melting point(s) (T_(m)) of each polymer isdetermined from the second heat curve (peak Tm), and the crystallizationtemperature (T_(c)) is determined from the first cooling curve (peakTc).

Gel Permeation Chromatography (GPC)

Conventional GPC measurements are used to determine the weight-average(Mw) and number-average (Mn) molecular weight of the polymer, and todetermine the MWD (=Mw/Mn). “Samples are analyzed with ahigh-temperature GPC instrument (Polymer Laboratories, Inc. modelPL220).

The method employs the well-known universal calibration method, based onthe concept of hydrodynamic volume, and the calibration is performedusing narrow polystyrene (PS) standards, along with four Mixed A 20 μmcolumns (PLgel Mixed A from Agilent (formerly Polymer Laboratory Inc.))operating at a system temperature of 140° C. Samples are prepared at a“2 mg/mL” concentration in 1,2,4-trichlorobenzene solvent. The flow rateis 1.0 mL/min, and the injection size is 100 microliters.

As discussed, the molecular weight determination is deduced by usingnarrow molecular weight distribution polystyrene standards (from PolymerLaboratories) in conjunction with their elution volumes. The equivalentpolyethylene molecular weights are determined by using appropriateMark-Houwink coefficients for polyethylene and polystyrene (as describedby Williams and Ward in Journal of Polymer Science, Polymer Letters,Vol. 6, (621) 1968) to derive the following equation:

Mpolyethylene=a*(Mpolystyrene)^(b).

In this equation, a=0.4316 and b=1.0 (as described in Williams and Ward,J. Polym. Sc., Polym. Let., 6, 621 (1968)). Polyethylene equivalentmolecular weight calculations were performed using VISCOTEK TriSECsoftware Version 3.0.

Fingerprint testing was conducted on compression molded plaques. Theappearance of fingerprints on the surface of the molded plaques wasdetermined by applying even, firm pressure with the thumb for 5 s to aplaque after sitting at room temperature for 1 day and 7 days or afterheat aging at 70° C. for 1 day and 7 days. For oven-aged samples, thefingerprint test was conducted immediately upon removal of the samplefrom the oven. The appearance of a fingerprint was evaluated using thefollowing scale: 1=no visible fingerprint, 2=marginally visiblefingerprint, and 3=clearly visible fingerprint.

Melt Index (MI) is measured in accordance with ASTM D 1238, Condition190° C./2.16 kg. Melt flow rate (MFR) is measured in accordance withASTM D 1238, Condition 230° C./2.16 kg.

Normalized oil-bleed index (NOBI) is an optical measurement to compareoil-bleed characteristics. Optical measurements are obtained accordingto the following procedure.

-   -   1. Test specimens in the form of approximately 3×6⅛×0.125 inch        specimens are cut from the compression molded plaques. Specimens        are cut from areas with minimal bubbles/dimples.    -   2. Within 2 hours of compression molding, the specimens are        overlaid with 3 pieces of ZigZag cigarette paper laid        side-to-side, with the length direction of the paper aligned        perpendicular to the length direction of the specimens. A sheet        of Mylar film is placed on the other side of the paper, so that        a sandwich is formed of Mylar film-paper-plaque.    -   3. The sandwich is placed in 40 or 60° C. ovens or at room        temperature in the laboratory, Mylar film layer down. Samples        are then aged for 24 hours, 1 week, and 2 weeks or 3 weeks. No        mass is present on top of the sample plaques, i.e., the force on        the paper is due to the mass of the plaque and gravity. The        samples are either supported by a laboratory countertop, the        base of the oven chamber, or a metal wire rack in the Thermo        oven. No additional support surface is present on the wire racks        so the force is concentrated on the wires of the rack, though        the Mylar sheet distributes it somewhat. The wires are        approximately ⅛ inch diameter and are spaced ¾ inch apart        (center to center).    -   4. Following aging, one of the three papers is removed from the        specimen and the specimen is returned to the oven until the        third paper is removed at the end of the aging period. Paper        removal is difficult in the case of samples with considerable        oil bleed since the paper is prone to tearing; if necessary, the        torn paper is pieced together as well as possible. The removed        paper from a given specimen is adhered (using double-sided tape)        to a standard approx. 9×12 inch sheet made from non-glossy black        compound.    -   5. Papers are scanned and analyzed as described below. First a        control sample is scanned (a new sheet of cigarette paper        attached to a plaque). Then, a paper sample from a plaque        sandwich is removed from the sandwich, mounted on the black        plaque as described above, and scanned. This is repeated for the        other samples. All samples are scanned as quickly as possible,        one after another, to minimize potential for scanner drift. Note        that the same black plaque is used for all samples, so the        mounting and analysis is done sequentially.    -   6. Scanning is performed using a Xerox WorkCentre M118i        copier/fax/scanner. The image is scanned in “Text” mode at 200        dpi, and saved as a TIFF file.    -   7. Method A. The TIFF file is opened in Microsoft Paint, cropped        on two sides, then saved. The image is then opened in Adobe        Photoshop CS2 (v. 9) and cropped on the other two sides. The        “text mode” image is a bitonal image. The percentage of black        pixels in the image was the desired result. This is conveniently        obtained in this software by first converting it to an 8-bit        greyscale image so that a greyscale histogram can be created,        with just 2 levels of greyscale, 0 (black) to 255 (white). The        percentile of the 0 greyscale level in the histogram is the same        as the percentage of black pixels. (This value was called “%        grey scale” but is actually a percentile and for the method as        described is equal to the “% black pixels” in the bitonal image.        The method works because Photoshop CS2 compresses large images        by combining 4 pixels into 1 greyscale pixel when using Cache        Level 2 thus creating 5 grey scale colors ranging from all white        to all black; the grey scale percentile in the histogram is thus        equivalent to the percent black pixels in the bitonal image).    -   Method B. As an alternative to and more direct method than        Method A, a bitonal image is opened with ImageJ software (v.        1.41) (National Institutes of Health) and the region of        cigarette paper selected using the select tool. Using the        Analyze\Set Measurement menu, “Area Fraction” is selected as a        desired output. Then, using the Analyze\Measure menu, the % Area        is reported for the selected image area. This % Area is the %        black pixels in the selected area.    -   8. This “% grey scale” (equal to % black pixels) is recorded        along with the images in an Excel spreadsheet for both the        control sheet as well as the paper sheets in contact with a        polymer specimen.

Molded plaques are aged for 24 hrs, 1 week and 2 weeks or 3 weeks (at23° C. and 60° C.) while resting on sheets of ZigZag cigarette paper.After aging, the cigarette paper is removed and optically scannedagainst a black background to measure the extent of oil-bleed. Anormalized oil-bleed index (NOBI) is calculated according to thefollowing equation:

Normalized Oil-bleed Index=100·(% grey scale sample−% grey scalecontrol)/(100−% grey scale control)

The term “% grey scale sample” is the percentile grey scale (% blackpixels) measured on the aged sample and “% grey scale control” is ameasurement on an unaged untreated sheet of cigarette paper. NOBI has arange from 0 to 100. When NOBI=100, the paper is saturated and the testdoes not register oil-bleed beyond that level. FIG. 1 shows fourexamples of grey scale: 20.1%, 34.6%, 51.6%, and 100% grey scale. If thefirst example (20.1%) is used as the control for normalization, thencorresponding NOBI values for these four images are 0%, 18.1%, 39.4% and100%.

Shore A hardness is measured on molded plaques in accordance with ASTM D2240. This test method permits hardness measurements based on eitherinitial indentation or indentation after a specified period of time, orboth. In the examples, a specified time of 10 seconds is used.

By way of example and not by limitation, examples of the presentdisclosure will now be provided.

Examples

The properties of the materials used in Example 1 are provided in Table2 below.

TABLE 2 Ingredient Component Specifications Source INFUSE ™OBC-ethylene/octene 0.5 MI, 0.866 g/cc density The Dow Chemical 9007block copolymer Company INFUSE ™ OBC-ethylene/octene 0.5 MI, 0.877 g/ccdensity The Dow Chemical 9010 block copolymer Company Hydrobrite ™ Oilmineral oil with nominal 70% paraffinic and 30% Sonneborn 550 naphtheniccontent, and average molecular weight of 541 g/mol H7012- PP 35 MFRpropylene homopolymer Braskem 35RN 5E16S PP 35 MFR propylene homopolymer(anti-stat grade) Braskem Zonyl FSN- surface-active agent Approximately950 molecular weight ethoxylated DuPont 100 nonionic fluorosurfactant at100% concentration. Based on fluorinated C4-C10 alkyl mixture. ZonylFSO- surface-active agent Approximately 725 molecular weight ethoxylatedDuPont 100 nonionic fluorosurfactant at 100% concentration. Based onfluorinated C4-C10 alkyl mixture. Capstone surface-active agent Nonionicfluorosurfactant at 100% concentration. DuPont FS-3100 DC 57surface-active agent 70-90 wt % dimethyl, methyl (polyethylene oxide DowCorning Additive acetate-capped) polysiloxane; 10-30 wt % polyethyleneglycol monoallyl ether acetate; <3 wt % polyethylene glycol diacetate PP= propylene-based polymer

Samples are prepared as follows:

Oil is imbibed into OBC polymer at 50-60° C. overnight, at a minimum.Compounding is accomplished using a HAAKE torque rheometer with a 190°C. Rheomix 3000E mixing bowl and roller blades at nominal mixing speedof 60 rpm for a period of 5-6 minutes after all of the formulationcomponents were added to the mixing bowl.

Compression molding is done at 190° C. using an approximately 125 milthick chase, using the following program:

-   -   2 minutes at 3000 psi    -   2 minutes at 5000 psi    -   5 minutes at 40,000 psi    -   Cool for 5 minutes at 40,000 psi

Samples are tested for hardness and oil bleed as previously described.

Molded plaques are aged (24 hrs, 1 week and 3 weeks at 23° C. and 60°C.) while resting on sheets of ZigZag cigarette paper. After aging, thecigarette paper is removed and optically scanned against a blackbackground to measure the extent of oil-bleed. The normalized oil-bleedindex (NOBI) is calculated.

The hardness of each sample is measured. The results are shown in Table3 below.

TABLE 3 Comp. Comp. Comp. Component/PHR A Inv. 1 B Inv. 2 Inv. 3 Inv. 4Inv. 5 C Inv. 6 Comp. D Inv. 7 Inv. 8 Comp. E Inv. 9 INFUSE ™ 9007 100100 100 100 100 100 100 100 100 INFUSE ™ 9010 100 100 100 100 100 PPH7012-35RN 50 50 50 50 50 50 50 50 50 50 PP 5E 16S 50 50 Hydrobrite 550150 150 150 150 150 150 150 233 233 150 150 150 233 233 Zonyl FSN100 5 50.5 Zonyl FSO100 5 Capstone FS3100 0.5 0.5 0.5 DC 57 0.5 0.5 TOTAL PHR250 255 300 305 305 300.5 300.5 383 383.5 300 300.5 300.5 383 383.5 NOBI41 9 10 0 0 2 0 76 11 0 2 13 18 0 1 day, 23° C. NOBI 88 34 13 0 0 13 0100 33 4 7 17 41 8 1 day, 60° C. NOBI 71 4 13 0 0 1 4 94 12 15 3 7 63 31 week, 23° C. NOBI 99 76 38 1 7 5 11 100 68 17 8 5 98 0 1 week, 60° C.NOBI 93 15 23 3 0 6 7 99 19 15 0 0 97 1 3 weeks, 23° C. NOBI 100 95 5810 16 13 38 100 96 18 4 3 100 30 3 weeks, 60° C. Fingerprint — — 3 — — 11 — — — — — — — 3 weeks, 23° C. Fingerprint — — 3 — — 1 3 — — — — — — —2 weeks, 60° C. Shore A Hardness 5 5 17 12 12 17 17 7 8 45 45 47 27 28PHR = parts per hundred

Results

Inventive Example 1 shows that addition of 5 phr (1.96 wt %) offluorosurfactant (Zonyl FSN-100) reduces oil bleed significantly after24 hours, with NOBI of 9 and 34 at 23° C. and 60° C., respectively. Oilbleed is also reduced at 1 week and 3 weeks at 23° C., but bleed-outremains high after 1 and 3 weeks at 60° C.

Comparative Sample B shows that inclusion of propylene homopolymer inthe formulation results in reduced oil bleed, with NOBI of 23 and 58after 3 weeks at 23° C. and 60° C., respectively. Addition of propylenehomopolymer reduces oil bleed but adversely affects the softness of thecompound (makes it harder). Thus, it is desirable to use only a moderateamount of propylene homopolymer such as in this comparative sample, andthen enhance the oil bleed resistance by other means. Formulations of100 parts INFUSE™ 9007, 150 parts oil, and 50 parts propylenehomopolymer exhibit about 15 Shore A hardness.

Inventive Examples 2-4 show that 5 phr (1.64 wt %) of fluorosurfactant(Zonyl FSN-100 or FSO-100) reduce oil bleed significantly as compared toComparative Sample B. Inventive Example 4 shows that 0.5 phr (0.17 wt %)Zonyl FSN-100 achieves a similar reduction in oil bleed. While notwishing to be bound by any particular theory, it is believed thatfluorosurfactant reduces oil bleed by reducing surface energy of thepolymer surface, thereby reducing propensity of oil to collect there.Provided sufficient surfactant is present to provide a low energysurface to the entire polymer surface, the desired effect is achievedand additional surfactant does not increase the oil bleed resistancefurther.

Inventive Example 5 shows that a polysiloxane surfactant is also aneffective surface-active agent for reducing oil bleed as compared toComparative Sample B. Furthermore, Inventive Example 8 shows that thesame polysiloxane surfactant is also effective at reducing oil bleed ina formulation with a different OBC and at a significantly higherhardness. Relative to Comparative Sample D, Inventive Example 8 hassimilar hardness, about 45 Shore A, but significantly lower oil bleedafter 1 and 3 weeks at 23 and 60° C.

Comparative Sample C and Inventive Example 6 have higher oil content,233 phr oil. Inventive Example 6, which contains 0.5 phr Capstone FS3100fluorosurfactant, has significantly lower oil bleed than ComparativeSample C, which does not contain a surfactant. The NOBI is low after 1day, 1 week, and 3 weeks at room temperature for Inventive Example 6,but there is oil bleed-out after aging at 60° C. for 1 week and 3 weeks.

Comparative Sample D has a similar composition in terms of oil andpolypropylene content as Comparative Sample B, but contains a differentOBC than Comparative Samples B. The use of INFUSE™ 9010 rather thanINFUSE™ 9007 results in lower oil bleed values and significantly higherhardness, 45 Shore A for Comparative Sample D compared to 17 Shore A forComparative Sample B. Similar to the other inventive examples, InventiveExample 7, which contains a fluorosurfactant, and Inventive Example 8,which contains a polysiloxane surfactant, both have significantly loweroil bleed than Comparative Sample D.

Comparative Sample E shows that oil bleed increases significantly whenhigher oil loading levels are used. Comparative Sample E contains 233phr oil versus Comparative Sample D, which contains 150 phr oil. The oilbleed can be reduced even at this higher oil loading level by includinga surfactant in the formulation. Inventive Example 9 contains 233 phroil and 0.5 phr of a fluorosurfactant and has low oil bleed at 23 and60° C. after 1 day, 1 week, and 3 weeks of aging.

In addition to reduced oil bleed, the inventive examples also havereduced stickiness as indicated by fingerprint testing. As described inthe methods section, the fingerprint test is a qualitative measurementof the visibility of a thumbprint on the surface of a molded plaquefollowing aging at a set temperature and time. A fingerprint rating of 1indicates no visible fingerprints, which correlates to a non-stickysurface. A fingerprint rating of 3 indicates a clearly visiblefingerprint, which correlates to a sticky surface. Inventive Examples 4and 5 show significantly reduced stickiness as measured by thefingerprint test as compared to Comparative Sample B. Inventive Example4 has reduced stickiness after aging at both 23 and 60° C., whileInventive Example 5 only has reduced stickiness after aging at 23° C.

It is specifically intended that the present disclosure not be limitedto the embodiments and illustrations contained herein, but includemodified forms of those embodiments including portions of theembodiments and combinations of elements of different embodiments ascome within the scope of the following claims.

1. An oil-extended olefin block copolymer composition comprising: anolefin block copolymer that is an ethylene/∝-olefin multi-blockcopolymer; an oil; and a surface-active agent.
 2. The composition ofclaim 1 wherein the olefin block copolymer has a density from 0.85 g/ccto 0.88 g/cc.
 3. The composition of claim 1 comprising from about 30 wt% to 70 wt % olefin block copolymer, from 30 wt % to 70 wt % oil, andfrom 0.01 wt % to 2.0 wt % surface-active agent.
 4. The composition ofclaim 1 wherein the surface-active agent is a fluorosurfactant.
 5. Thecomposition of claim 1 wherein the surface-active agent is apolysiloxane surfactant.
 6. The composition of claim 1 having a Shore Ahardness from 5 to
 50. 7. The composition of claim 1 having a normalizedoil-bleed index (NOBI) of less than 30 after 1 week at 23° C.
 8. Thecomposition of claim 1 having a normalized oil-bleed index (NOBI) ofless than 30 after 3 weeks at 23° C.
 9. An oil-extended olefin blockcopolymer composition comprising: an olefin block copolymer that is anethylene/∝-olefin multi-block copolymer; from 70 phr to 250 phr of anoil; from 0.05 phr to 5 phr of a surface-active agent; and thecomposition has a Shore A hardness from 5 to 50 and a normalizedoil-bleed index of less than or equal to 30 after three weeks at 23° C.10. The composition of claim 9 comprising 150 phr oil.
 11. Thecomposition of claim 9 comprising from 0.5 phr to 5 phr surface-activeagent.
 12. An oil-extended olefin block copolymer compositioncomprising: an olefin block copolymer that is an ethylene/∝-olefinmulti-block copolymer; an olefin-based polymer; an oil; and asurface-active agent.
 13. The composition of claim 12 wherein theolefin-based polymer is a propylene homopolymer.
 14. The composition ofclaim 12 comprising from 10 wt % to 40 wt % olefin block copolymer; from5 wt % to 25 wt % propylene homopolymer; from 15 wt % to 60 wt % oil;and from 0.01 wt % to 2.0 wt % surface-active agent.
 15. The compositionof claim 12 wherein the olefin-based polymer is a high densityethylene-based polymer.